245 research outputs found
Quantifying constraints determining independent activation on NMDA receptors mediated currents from evoked and spontaneous synaptic transmission at an individual synapse
A synapse acts on neural transmission through a chemical process called
synapses fusion between pre-synaptic and post-synaptic terminals. Presynaptic
terminals release neurotransmitters either in response to action potential or
spontaneously independent of presynaptic activity. However, it is still unclear
the mechanism of evoked and spontaneous neuro-transmission that activate on
postsynaptic terminals. To address this question, we examined the possibility
that spontaneous and evoked neurotransmissions using mathematical simulations.
We aimed to address the biophysical constraints that may determine independent
activation on N-methyl-D-asparate (NMDA) receptor mediated currents in response
to evoked and spontaneous glutamate molecules releases. In order to identify
the spatial relation between spontaneous and evoked glutamate release, we
considered quantitative factors, such as size of synapses, inhomogeneity of
diffusion mobility, geometry of synaptic cleft, and release rate of
neurotransmitter. Simulation results showed that as a synaptic size is smaller
and if the cleft space is more cohesive in the peripheral area than the centre
area, then there is high possibility of having crosstalk of two signals
released from center and edge. When a synaptic size is larger, the cleft space
is more affinity in the central area than the external area, and if the
geometry of fusion has a narrower space, then those produce more chances of
independence of two modes of currents released from center and edge. The
computed results match well with existing experimental findings and serve as a
road map for further exploration to identify independence of evoked and
spontaneous releases
DAppSCAN: Building Large-Scale Datasets for Smart Contract Weaknesses in DApp Projects
The Smart Contract Weakness Classification Registry (SWC Registry) is a
widely recognized list of smart contract weaknesses specific to the Ethereum
platform. Despite the SWC Registry not being updated with new entries since
2020, the sustained development of smart contract analysis tools for detecting
SWC-listed weaknesses highlights their ongoing significance in the field.
However, evaluating these tools has proven challenging due to the absence of a
large, unbiased, real-world dataset. To address this problem, we aim to build a
large-scale SWC weakness dataset from real-world DApp projects. We recruited 22
participants and spent 44 person-months analyzing 1,199 open source audit
reports from 29 security teams. In total, we identified 9,154 weaknesses and
developed two distinct datasets, i.e., DAPPSCAN-SOURCE and DAPPSCAN-BYTECODE.
The DAPPSCAN-SOURCE dataset comprises 39,904 Solidity files, featuring 1,618
SWC weaknesses sourced from 682 real-world DApp projects. However, the Solidity
files in this dataset may not be directly compilable for further analysis. To
facilitate automated analysis, we developed a tool capable of automatically
identifying dependency relationships within DApp projects and completing
missing public libraries. Using this tool, we created DAPPSCAN-BYTECODE
dataset, which consists of 6,665 compiled smart contract with 888 SWC
weaknesses. Based on DAPPSCAN-BYTECODE, we conducted an empirical study to
evaluate the performance of state-of-the-art smart contract weakness detection
tools. The evaluation results revealed sub-par performance for these tools in
terms of both effectiveness and success detection rate, indicating that future
development should prioritize real-world datasets over simplistic toy
contracts.Comment: Dataset available at https://github.com/InPlusLab/DAppSCA
Turn the Rudder: A Beacon of Reentrancy Detection for Smart Contracts on Ethereum
Smart contracts are programs deployed on a blockchain and are immutable once
deployed. Reentrancy, one of the most important vulnerabilities in smart
contracts, has caused millions of dollars in financial loss. Many reentrancy
detection approaches have been proposed. It is necessary to investigate the
performance of these approaches to provide useful guidelines for their
application. In this work, we conduct a large-scale empirical study on the
capability of five well-known or recent reentrancy detection tools such as
Mythril and Sailfish. We collect 230,548 verified smart contracts from
Etherscan and use detection tools to analyze 139,424 contracts after
deduplication, which results in 21,212 contracts with reentrancy issues. Then,
we manually examine the defective functions located by the tools in the
contracts. From the examination results, we obtain 34 true positive contracts
with reentrancy and 21,178 false positive contracts without reentrancy. We also
analyze the causes of the true and false positives. Finally, we evaluate the
tools based on the two kinds of contracts. The results show that more than
99.8% of the reentrant contracts detected by the tools are false positives with
eight types of causes, and the tools can only detect the reentrancy issues
caused by call.value(), 58.8% of which can be revealed by the Ethereum's
official IDE, Remix. Furthermore, we collect real-world reentrancy attacks
reported in the past two years and find that the tools fail to find any issues
in the corresponding contracts. Based on the findings, existing works on
reentrancy detection appear to have very limited capability, and researchers
should turn the rudder to discover and detect new reentrancy patterns except
those related to call.value().Comment: Accepted by ICSE 2023. Dataset available at
https://github.com/InPlusLab/ReentrancyStudy-Dat
Multi-objective scheduling of a steelmaking plant integrated with renewable energy sources and energy storage systems: Balancing costs, emissions and make-span
As an energy-intensive industry, the steel industry grapples with increasing energy costs and decarbonisation pressures. Therefore, multi-objective optimisation is widely applied in the production scheduling of the steelmaking plant. However, the optimal solution prioritising energy savings and emission reductions may lead to impractical or less economically efficient solutions, since the processing time requirement (PTR) of steel production orders in real-world production is neglected. This study fills the research gap by discussing the impact of PTR on the make-span of the steelmaking process and incorporating it into the optimisation model. Considering the variability of PTR, the solving of the multi-objective scheduling problem is transformed into the selection from Pareto solutions with different make-spans. To better leverage the temporal flexibility of the steelmaking process, a what-if-analysis-based strategy coupled with the Normal Boundary Intersection method is proposed to generate a series of evenly distributed Pareto solutions. The energy storage system is integrated to improve the time granularity of the steelmaking plant's flexibility. Our case studies demonstrate that the electricity and emission costs are reduced by 68.5%, indirect emissions are reduced by 83.5%, and the on-site renewable energy self-consumption rate increases by 12.1%. The effectiveness of the proposed method implies that it is of great relevance to the development of a cleaner steel industry in the future
AutoAlign: Fully Automatic and Effective Knowledge Graph Alignment enabled by Large Language Models
The task of entity alignment between knowledge graphs (KGs) aims to identify
every pair of entities from two different KGs that represent the same entity.
Many machine learning-based methods have been proposed for this task. However,
to our best knowledge, existing methods all require manually crafted seed
alignments, which are expensive to obtain. In this paper, we propose the first
fully automatic alignment method named AutoAlign, which does not require any
manually crafted seed alignments. Specifically, for predicate embeddings,
AutoAlign constructs a predicate-proximity-graph with the help of large
language models to automatically capture the similarity between predicates
across two KGs. For entity embeddings, AutoAlign first computes the entity
embeddings of each KG independently using TransE, and then shifts the two KGs'
entity embeddings into the same vector space by computing the similarity
between entities based on their attributes. Thus, both predicate alignment and
entity alignment can be done without manually crafted seed alignments.
AutoAlign is not only fully automatic, but also highly effective. Experiments
using real-world KGs show that AutoAlign improves the performance of entity
alignment significantly compared to state-of-the-art methods.Comment: 14 pages, 5 figures, 4 tables. arXiv admin note: substantial text
overlap with arXiv:2210.0854
Adeno-associated virus serotype rh.10 displays strong muscle tropism following intraperitoneal delivery
Recombinant adeno-associated virus (rAAV) is an attractive tool for basic science and translational medicine including gene therapy, due to the versatility in its cell and organ transduction. Previous work indicates that rAAV transduction patterns are highly dependent on route of administration. Based on this relationship, we hypothesized that intraperitoneal (IP) administration of rAAV produces unique patterns of tissue tropism. To test this hypothesis, we investigated the transduction efficiency of 12 rAAV serotypes carrying an enhanced green fluorescent protein (EGFP) reporter gene in a panel of 12 organs after IP injection. Our data suggest that IP administration emphasizes transduction patterns that are different from previously reported intravascular delivery methods. Using this approach, rAAV efficiently transduces the liver, pancreas, skeletal muscle, heart and diaphragm without causing significant histopathological changes. Of note, rAAVrh.10 showed excellent muscle transduction following IP administration, highlighting its potential as a new muscle-targeting vector
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